Sensory Processing Disorder Subtypes

Sensory Modulation Disorder

As the most common Sensory Disorder, children with this disorder will have difficulty regulating responses to sensory input - responses are not adjusted to the situation well. The child will have difficulty maintaining a calm state to adapt to daily life activities. We have a detailed blog post about this condition click here.

Sensory Discrimination Disorder

This is when a child has difficulty telling the difference or similarities (size, quality, temperature, shape and texture etc) of sensory stimuli. The child’s central nervous system may not get correct sensory messages, which makes it harder to be purposeful during activities and relate successfully to other people. For example, they might not get the right information about how high is the step, how loud is their voice, how full is their mouth, how much force is used to hold a pencil/add blocks to structure/kick a ball or lean on a friend. Recognising and interpreting sensory stimuli may take more time or more effort for the child. Common behavioural signs:

  • Is unable to dress quickly
  • Has poor handwriting skills 
  • Difficulty following detailed directions or slow to respond (not able to distinguish where the sound is coming from)
  • Reads slowly
  • Afraid of swing or jumping (unable to judge distance)
  • Is a picky eater
  • Refuses to go to certain places 

Sensory-Based Motor Disorder 

This is when a child has a motor disorder due to underlying sensory dysfunction. The motor disorder could range from lack of postural control, poor core strength, problems with quality of movements, weaknesses in stabilising their joints and body etc due to sensory differences most common in touch, proprioceptive (body awareness), vestibular (movement & balance) sensory domains. The child can also have problems with praxis. They present as having appropriate core muscles but instead have trouble coming up with ideas for motor actions, planning, sequencing and executing unfamiliar precise movement actions. Sometimes also called motor planning. This can result in awkward and poorly coordinated motor skills. As well as difficulties timing their movements correctly.

Common behavioural signs:

  • W sitting 
  • Weaker muscles and poor sense of where body is in space 
  • Poor bilateral coordination (using both sides of his body together)
  • Problems with rotating trunk
  • Difficulties crossing midline of body to reach for objects 
  • Decreased balance 
  • Wandering the room with upright posture and unsure how to use the space, equipment or toys 
  • Strong desire for sameness or routines and demonstrate simple motor patterns during play e.g. dumping toys, collecting toys in his/ her hands
  • Difficulties using both eyes to smoothly follow an object in space 
  • Difficulty following multistep directions

Emily Nguyen is a Paediatric Occupational Therapist and caregiver to her little brother who has Autism Spectrum Disorder. She writes from the perspective of her experience as a therapist as well as a caregiver to a special needs family member. The blog posts are intended to inspire and educate but are in no way intended to offer medical or mental health advice. Please see disclaimer for details.